firewire: replace subtraction with bitwise and

Replace an unnecessary subtraction with a bitwise AND when determining the
value of ext_tcode in fw_fill_transaction() to save a cpu cycle or two in a
somewhat critical path.

Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

diff --git a/drivers/firewire/fw-transaction.c b/drivers/firewire/fw-transaction.c
index 8018c3b9df0f834d2307cd768fb708bc8af0aaa8..7fcc59dedf08cfa038d652336d1f85383614ccd3 100644 (file)
--- a/drivers/firewire/fw-transaction.c
+++ b/drivers/firewire/fw-transaction.c
@@ -153,7 +153,7 @@ fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
        int ext_tcode;
 
        if (tcode > 0x10) {
-               ext_tcode = tcode - 0x10;
+               ext_tcode = tcode & ~0x10;
                tcode = TCODE_LOCK_REQUEST;
        } else
                ext_tcode = 0;